Personal electronic devices having relatively large display screens are becoming increasingly popular. For example, many cellular telephones and portable tablet devices now have display screens that comprise most or all of the entire front face of the device. Particular examples of such devices include the iPhone® and iPad® product lines that are offered by Apple Inc. of Cupertino, Calif. Similarly, many laptop computers have display screens that comprise much or all of the entire top half of the overall device. Such designs advantageously tend to maximize the size of the display screen for a given device footprint, which is an attractive feature for many consumers.
Of course, various issues must be taken into account when designing a device with such a relatively large display screen. In addition to sizing, support and aesthetic appearance considerations, many device makers also desire to provide some sort of protection with respect to the front face of the display, particularly where the front face may also include a touch screen type of input for the user. This is often accomplished by providing a flat, thin, and transparent outer display cover or “cover glass” that is separate from the actual display component or device itself. Such an outer display cover can be relatively inexpensive in comparison with a full display component or device, such that scratches, cracks or other damage to the outside of the device can typically be remedied by repairing or replacing the outer cover glass rather than the entire internal display device.
Such an outer display cover and internal display device arrangement often includes a gasket, seal, enclosed space, or other similar protection between the two closely placed items. This seal or other protection tends to ward against moisture, dust and other contaminants that may get trapped between the display cover and internal display device screen, which contaminants could then result in a less optimal or even unusable display for the device user.
Unfortunately, the ability to effect a suitable seal or other similar protection can be challenging within the context of the mass production of devices. Even slight defects or small variances in part dimensions from device to device can lead to enough of a misalignment between an individual display device and cover glass to cause problems. The resulting poor sealing or uneven gasket compression can then cause eventual condensation, contamination or other negative effects with respect to the display. These display alignment issues can be exacerbated as the display size increases, such that the relatively large displays of many tablet devices and laptop computers can be particularly impacted. Solutions can involve imposing tighter tolerances and restrictions on individual parts and features, although this can then lead to more inconvenience and higher manufacturing costs.
While many designs and techniques used to provide protective seals for relatively large display screens on electronic and computing devices have generally worked well in the past, there is always a desire to provide improvements in such designs and techniques. Therefore, the ability to accurately align components during device manufacture to result in reliable protective seals on computing devices having large display screens without requiring unduly tight part tolerances is desired.